1. Field of the Invention
The present invention relates to multi-user wireless voice communication methods and systems and more particularly pertains to a new wireless communication system adapted to permit many users to speak simultaneously while hearing every other user; the system and method of the present invention are especially well suited for use in tactical or potentially hazardous situations or environments.
2. Discussion of the Prior Art
Prior art multi-user wireless voice communication systems commonly use a push-to-talk (PTT) design wherein each user's radio or communication device disables its receiver when its transmitter is transmitting the user's spoken communications. PTT radios are often configured as “walkie-talkies” and have a button on one side of a housing for the user to press when speaking. Walkie-talkie users must deal with gaps in reception corresponding to their chosen speaking interval, and so a cumbersome ritual is followed in which each user completes his or her spoken message with a phrase “over” indicating that other users may speak, and that speaker is now prepared to listen.
In tactical or hazardous situations, especially when three or more users must share a communications system, this method is burdensome, in part because a user with time-sensitive emergent information may not be able to clear another speaker from the channel and so is effectively blocked from communicating. If the user attempting to communicate about the emergency does successfully transmit, at least one other user, the interrupted speaker, will not hear.
Some wireless communication systems employ voice-activated PTT circuitry (also known as “VOX” circuitry) to enable one user's transmitter while blocking other users' transmitters. If more than one user speaks up at a given time, the second user may be blocked. VOX activation is a feature widely used in communications systems employing hands-free headsets, such headsets typically include at least one microphone and at least one ear speaker.
In tactical situations, users in an assault team may be spread out to surround an objective and may not be able to see one another. Each user may have a unique perspective. For example, if a building is being assaulted, three or more users on the ground may need to communicate with an observer hovering overhead in a helicopter. Any one of those users may need to shout a warning to another user instantly, irrespective of whether the user to be warned is speaking at that moment, and all users in the assault team may need to hear every contribution to the conversation, even if simultaneously spoken. In the stress and heat of an engagement, hearing both sides of a shouting match between users may be vital to the survival of one or all the users.
First responders in civil emergencies have similar needs, Firemen entering a large, damaged structure need to find injured or helpless occupants as quickly as possible and may require members of a team entering the structure to be able to communicate in real time and simultaneously so that the users can support and come to the aid of one another.
Similarly, police or SWAT team members will require an improved method of communicating. Police or SWAT team members entering a structure or area occupied by moving, hostile criminals may need to find injured occupants or hostages quickly and may require members of the team entering the area to be able to communicate in real time and simultaneously so that the team members can identify hostile actors or targets and support and come to the aid of one another, as a situation develops.
There is a need, therefore, for an economical, reliable, truly robust and easy to use multi-user voice communication system and method suitable for use in rapidly evolving tactical or hazardous situations, permitting each user to hear every voice communication occurring among the other users, no matter when each user speaks, and no matter how many users try to speak at once. One may characterize this as a need for a “party-line” radio system, so named because it should work like a party-line telephone service, where all can hear every speaker, even when all users are speaking simultaneously.
Ideally, the system should be transportable and operable without requiring an elaborate set-up procedure requiring installation of a central hub or router for controlling a varying number of users when moving.